WPF and Silverlight 学习笔记（十六）：WPF资源（Resource）（1）

一、什么是资源

通常使用 WPF 资源作为重用通常定义的对象和值的简单方法。例如定义一种可以复用的单色的Brush对象，按钮的背景及矩形的填充颜色均使用此Brush：

   1: <Window x:Class="WPFResource.WinBasicResource"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     Title="Basic Resource" Height="200" Width="300">
   5:     <Window.Resources>
   6:         <SolidColorBrush x:Key="myBrush" Color="Gold" />
   7:     </Window.Resources>
   8:     <StackPanel>
   9:         <Button Margin="5" Content="Sample Button" Background="{StaticResource myBrush}" />
  10:         <Rectangle Margin="5" Width="100" Height="100" Fill="{StaticResource myBrush}" />
  11:     </StackPanel>
  12: </Window>

在WPF中资源通常用作“样式”（Style）、样式模板、数据模板等。

二、资源的定义及XAML中引用

资源可以定义在以下几个位置：

  • 应用程序级资源：定义在App.xaml文件中，作为整个应用程序共享的资源存在

在App.xaml文件中定义：

   1: <Application x:Class="WPFResource.App"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     StartupUri="Window1.xaml">
   5:     <Application.Resources>
   6:         <SolidColorBrush Color="Gold" x:Key="myGoldBrush" />
   7:     </Application.Resources>
   8: </Application>

在ApplicationResourceDemo.xaml文件（窗体）中使用App.xaml中定义的Resource

   1: <Window x:Class="WPFResource.ApplicationResourceDemo"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     Title="Application Resource Demo" Height="300" Width="300">
   5:     <StackPanel>
   6:         <Button Margin="5" Background="{StaticResource myGoldBrush}">Sample Button</Button>
   7:     </StackPanel>
   8: </Window>
  • 窗体级资源：定义在Window或Page中，作为一个窗体或页面共享的资源存在 
   1: <Window x:Class="WPFResource.WindowResourceDemo"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     Title="WindowResourceDemo" Height="300" Width="300">
   5:     <Window.Resources>
   6:         <SolidColorBrush x:Key="myRedBrush" Color="Red" />
   7:     </Window.Resources>
   8:     <StackPanel>
   9:         <Button Margin="5" Background="{StaticResource myRedBrush}">Sample Button</Button>
  10:     </StackPanel>
  11: </Window>
  • 文件级资源：定义在资源字典的XAML文件中，再引用

在Visual Studio的WPF应用程序项目中，添加“资源字典（Resource Dictionary）”类型的项

AddResourceDictionary

在其XAML文件中定义：

   1: <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   2:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
   3:     <SolidColorBrush x:Key="myWhiteBrush" Color="White" />
   4: </ResourceDictionary>

在FileResourceDemo.xaml文件（窗体）中，将其注册为窗体级的资源，并引用

   1: <Window x:Class="WPFResource.FileResourceDemo"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     Title="FileResourceDemo" Height="300" Width="300">
   5:     <Window.Resources>
   6:         <ResourceDictionary Source="MyResourceDictionary.xaml" />
   7:     </Window.Resources>
   8:     <StackPanel>
   9:         <Button Margin="5" Background="{StaticResource myWhiteBrush}">Sample Button</Button>
  10:     </StackPanel>
  11: </Window>
  • 对象（控件）级资源：定义在某个ContentControl中，作为其子容器、子控件共享的资源

在Button中定义一个资源，供Button内的Content控件使用

   1: <Window x:Class="WPFResource.ControlResourceDemo"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     Title="ControlResourceDemo" Height="300" Width="300">
   5:     <StackPanel>
   6:         <Button Margin="5">
   7:             <Button.Resources>
   8:                 <SolidColorBrush x:Key="myGreenBrush" Color="Green" />
   9:             </Button.Resources>
  10:             <Button.Content>
  11:                 <TextBlock Text="Sample Text" Background="{StaticResource myGreenBrush}" />
  12:             </Button.Content>
  13:         </Button> 
  14:     </StackPanel>
  15: </Window>

三、XAML解析资源的顺序

在XAML中解析资源按照由引用资源的控件向外层容器依次调用资源。例如在在应用程序级别、窗体级别及对象级别分为定义x:Key相的同资源：

在App.xaml文件中：

   1: <Application x:Class="WPFResource.App"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     StartupUri="MultiResourceReference.xaml">
   5:     <Application.Resources>
   6:         <!-- 应用程序级资源 -->
   7:         <SolidColorBrush Color="Gold" x:Key="myGoldBrush" />
   8:         <SolidColorBrush Color="Blue" x:Key="myBrush" />
   9:     </Application.Resources>
  10: </Application>

在窗体的XAML文件中：

   1: <Window x:Class="WPFResource.MultiResourceReference"
   2:     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   3:     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   4:     Title="MultiResourceReference" Height="265" Width="300">
   5:     <Window.Resources>
   6:         <!-- 窗体级资源 -->
   7:         <SolidColorBrush Color="White" x:Key="myWhiteBrush" />
   8:         <SolidColorBrush Color="Green" x:Key="myBrush" />
   9:     </Window.Resources>
  10:     <StackPanel>
  11:         <!-- 使用应用程序级定义的资源 -->
  12:         <Button Margin="5" Content="Sample Button" Background="{StaticResource myGoldBrush}" />
  13:         
  14:         <!-- 使用窗体级定义的资源 -->
  15:         <Button Margin="5" Content="Sample Button" Background="{StaticResource myWhiteBrush}" />
  16:         
  17:         <!-- 窗体级资源的值覆盖应用程序级资源的值 -->
  18:         <Button Margin="5" Content="Sample Button" Background="{StaticResource myBrush}" />
  19:         
  20:         <StackPanel Background="#FF999999">
  21:             <StackPanel.Resources>
  22:                 <!-- 对象级资源 -->
  23:                 <SolidColorBrush Color="Yellow" x:Key="myYellowBrush" />
  24:                 <SolidColorBrush Color="Red" x:Key="myBrush" />
  25:             </StackPanel.Resources>
  26:  
  27:             <!-- 使用应用程序级定义的资源 -->
  28:             <Button Margin="5" Content="Sample Button" Background="{StaticResource myGoldBrush}" />
  29:  
  30:             <!-- 使用窗体级定义的资源 -->
  31:             <Button Margin="5" Content="Sample Button" Background="{StaticResource myWhiteBrush}" />
  32:  
  33:             <!-- 使用对象级定义的资源 -->
  34:             <Button Margin="5" Content="Sample Button" Background="{StaticResource myYellowBrush}" />
  35:  
  36:             <!-- 使用对象级定义的资源覆盖窗体级、应用程序级定义的资源 -->
  37:             <Button Margin="5" Content="Sample Button" Background="{StaticResource myBrush}" />
  38:         </StackPanel>
  39:     </StackPanel>
  40: </Window>

MultiResourceReference

未完待续…

posted @ 2009-04-21 13:15  龙腾于海  阅读(9765)  评论(5)  编辑  收藏  举报